南图尔盖盆地Karabulak油田基底碳酸盐岩储层结构复杂、孔隙空间类型多样、非均质性极强,利用单一的常规测井方法对该类储层进行识别一直是测井解释的难点。利用深侧向电阻率、声波时差、密度、补偿中子等多条常规测井曲线的响应特征进行重构,并结合改进后的曲线变化率法,总结出了碳酸盐岩裂缝型储层、孔洞型储层和缝洞型储层在常规测井曲线上的响应规律,提出了一种针对研究区碳酸盐岩缝洞型储层的测井评价新方法。应用这一方法对研究区的X1、X2和X3井开展储层划分与评价,结果表明研究区碳酸盐岩储层类型主要为缝洞型。通过与试油结论和成像测井识别结果进行对比,研究提出的方法准确识别出了裂缝、孔洞发育的地层,显著提高了对研究区缝洞识别的效率和精度。

The basement carbonate reservoirs in the Karabulak oil field of the South Turgai Basin have the characteristics of complex structure, variety of pore type and strong heterogeneity. The identification of such reservoirs by single conventional logging method is always a difficult point in logging interpretation. In this paper, the response characteristics of conventional logging curves such as deep lateral resistivity, acoustic time difference, density and compensated neutron were used for reconstruction. Combined with the improved method of curve change rate, the response laws of fractured carbonate reservoirs, pore-cave reservoirs and fractured vuggy reservoirs on conventional logging curves were summed up, respectively. And a new logging evaluation method for carbonate fractured vuggy reservoirs in the Karabulak oil field of South Turgai Basin was proposed. This method was used to identify reservoirs in X1, X2 and X3 wells of this oilfield. The results show that the carbonate reservoirs in this area are mainly fractured-vuggy type. Compared with the oil test conclusion and imaging logging, the method proposed in this paper accurately divided the reservoir type. And the efficiency and accuracy of the reservoir division have been greatly improved.